DESCRIPTION (Applicant's Description): This program supports research training at the post-doctoral level primarily focused on cancer, biology, radiation biology, and radiological physics relevant to therapeutic radiology. The training program is of two years duration. The program in radiation biology is open to individuals who hold the Ph.D. degree in one of the basic biological sciences, biochemistry, molecular biology, cell biology, molecular genetics, classical radiation biology, etc. who wish to pursue cancer-related studies, particularly as applied to therapeutic radiology, and to individuals who hold the M.D. degree who wish to pursue careers in combining laboratory and clinical research in these same areas. The program in radiological physics is designed to train post- doctoral physicists in those aspects of dosimetry, radioactivity, diagnostic imaging, instrumentation and computers which are applicable to radiation therapy. The programs take advantage of the extensive laboratory and clinical research activity in the Department of Therapeutic Radiology. The program includes formal courses in therapeutic radiology, radiation biology, radiological physics, and in scientific ethics. Trainees are assigned to research groups and devote more than 90% of their time to specific long-term research projects. Trainees interact with a wide variety of other biomedical science research programs throughout Yale University and the Yale Comprehensive Cancer Center.